13x40 lathe headstock spindle bearings

[PeterT]

There is a part 1 and 2 btw. Kind of interesting. I've read a few forum articles & CNC conversions but there isn't as much tear down/rebuild detail on our typical Asian hobby machines on YouTube.

Some takeaway points for me:

- replacement spec bearings are not exactly cheap. One may argue he didn't have to replace them all, but I see the point. The majority of cost was spindle bearings & if you're in that deep, maybe just do them all especially with grit circulation issues.

- I was led to believe Jet was predominantly/all Taiwan machines, supposedly better overall quality vs. similar looking Chinese models. This is (hopefully) is true with some of the components themselves. But this unfortunately shows similar corner cutting issues which can culminate to grief down the road.

- the (Jet) replacement costs were significantly more than what he was able to source elsewhere. One I believe he said same spec came from Grizzly. I wonder if cost is related to these particular sizes are more obscure or that's reality for this class of precision bearing? Eventually he found what he needed but seems like 5 different sources.

- this was just the bearings, the gears were deemed OK. I guess just because a machine looks 'ok' on the outside, you have no idea whats under the hood without running it. Just like a project car or plane, could be a money pit time bomb. I'd consider a project machine one day but this reinforces my view that one should have prior line of sight that parts can be available and fits the budget. Either through vendors (depends on vintage) or harvested from donor machines (depends on general availability and price). One can recondition or re-make lots of parts with existing machines, but you cant fix or make a precision bearing yourself & might even be challenged on certain gears especially if they need to be hardened.

Anyways, enjoy. He's kind of an entertaining character.

 

[RobinHood]

I did watch the video. Waiting for part 2...

kind of why I’d much rather have an old, dirty, original paint machine including all the dings, bumps and bruises than something used from a vendor that was pressure washed, sand blasted, if they went the extra mile, and slapped on a new coat of paint before the sale. Sure, looks pretty on the outside, but the insides could all be shot, costing you thousands more after you discover it.

at least the rough looking ones may go for a reasonable price so if it does require some work/parts, then you may actually end up with a mechanically very good machine. Also, for me anyway, it gives the incentive to “tear into it”, to give it a very good cleaning and inspection, repair as required and reassembly. Then you learn how the thing actually works and can discover some of the clever/not so good design features. At the same time, you can see what could be the limitations (because of the design) and, during use, not over stress / damage the machine because you know the potential weak point.

example: the oiling system of the headstock on the Colchester Master. The pump feeds low pressure oil through a tube to the various bearings, clutches and gears. The original design used t-offs of equal size resulting in the first gear getting most of the flow, the FWD clutch getting some, the REV clutch getting a little and the last gear/bearing getting just a few drops once in a while. Overall, was it good enough - probably, as everything gets splashed around anyway. Could it be better, sure. Ended up putting simple restrictors of different sizes in each t-off to equalize flow. Now all components are happy and the headstock is very quiet; not very common on these lathes apparently, so I have read.